A jury tasked with determining whether two Northland men are guilty of murdering Jack Davis with a thistle grubber have retired to consider their verdicts.

Justice Edwin Wylie finished summing up the seven-week trial this morning and the jury retired to begin its deliberations.

The Crown says Neville Dangen and Wayne Bracken kidnapped and murdered the 30-year-old Northland father. His body was found off the Wairakau walking track, on the northern side of the Whangaroa Harbour on February 25 last year.

Yesterday, the High Court at Whangarei heard that Dangen was paralysed by fear after being stood over by Bracken, who was "menacing, scary and evil".

Lawyer Mike Dodds made the statement in his closing address, as he summed up the defence case for 24-year-old Dangen.

Mr Dodds said Mr Davis did not deserve to die but he did because he got involved with the wrong man - Bracken.

"There is nothing rational about Jack Davis' death. Tragically, this is just a shocking cold-blooded killing for no reason, other than Mr Wayne Bracken's violent switch got flicked to on. And once that was flicked on, there was no stopping the tragic events that followed."

Mr Dodds said Dangen did nothing to assist Bracken in the kidnapping of Mr Davis and it was not Dangen who struck the killer blows - that was Bracken. Dangen had a lucky escape from becoming the next victim of Bracken's "delusional, extreme, violence", he said.

The Crown pointed out there were numerous times Dangen could have raised the alarm when Bracken was not around.

Mr Dodds asked the jury not to judge Dangen harshly for his inaction, as he feared Bracken.

An ESR scientist gave evidence that a partial shoe print matching that of a sandal worn by Dangen was found seven metres away from Mr Davis' body in the bush. Mr Dodds said the scientist said the impression provided "moderate support" that it was from Dangen's shoe.

However, Mr Dodds said that could have been left when Dangen returned to the track with three others to try to find Mr Davis after police had been alerted.

Dangen had no previous convictions prior to the incident. He was fully co-operative with the police and gave a series of taped interviews and allowed police to seize his cellphone, clothing and sandals, which were taken from him even though he had not been arrested, Mr Dodds said.

Bracken's evidence on the stand was "concocted" and should be rejected, Mr Dodds said.

Justice Wylie also began his summary of the case in which more than six weeks of evidence has been heard.

He began a detailed summary of the law and how the jury could apply the evidence, which wrapped up this morning.